Atmospheric Plasma treatment, effect on the plasma chemistry on adhesion Nicolas Vandencasteele

Transcription

1 1 oating Plasma Innovation Atmospheric Plasma treatment, effect on the plasma chemistry on adhesion Nicolas Vandencasteele

2 2 Plasma Applications Adhesion improvement onclusion

3 3 Plasma 4 th state of matter: ionized gas

4 4 old atmospheric plasma old: T gas < 100 T ions,neutrals < 100 T electrons Hot: T gas T ions,neutrals T electrons 10 4 <T<10 8 Atmospheric: Plasma gas is at atmospheric pressure pen reactor, high density of particles Energetic electrons chemistry

5 5 orona High Voltage Used for activation or cleaning Flat substrate Most of the time need to be used inline with other process Gas used: none (ambient air) Ambient air Filamentary discharge

6 6 Plasma DBD High Voltage Used for activation or cleaning and deposition Flat substrate Used online or offline Gas used:n 2, (Ar, He) ontrolled atmosphere Homogeneous discharge

7 7 Plasma vs orona Surface energy measurements on BPP film ontrolled chemistry Stable treatment

8 8 Plasma vs orona Microscopy (AFM) image of BPP film 1 µm x 1 µm images (Tapping) Untreated Plasma DBD orona Es 30 mn/m Es = 60 mn/m Es = 38 mn/m Identical discharge power ontrolled chemistry, homogenous discharge no surface damage

9 9 Process Plasma gas + dopant Dopant: ppm of reactive gases mixed with plasma gas (only safe gas green top bottles)

10 10 APPLIATINS

11 11 Applications: leaning Plasma 2, H 2 ontaminated surface Surface contamination leaned sample Removal of surface contamination without substrate degradation

12 12 Applications: Grafting H H Amine Amide Imide N H H 2 NH N H Gas: N 2 + dopants Surface functionalization

13 13 Applications: Grafting Atomic % (XPS) Quantity (a.u.) Standard Dopant 1 Advanced 1 Dopant 2 Advanced Amine Amide Imide Grafting of nitrogen containing groups Tunable surface functionalization

14 14 Applications:oating Specific molecules (precursor ) are added to the plasma gas. Those molecules are activated ( ) by the plasma and react with the sample surface to form a thin film. HMDS precursor Si x film (hydrophilic) Si y x film (hydrophobic) oating nature dependend on precursor AND plasma chemistry

15 15 ADHESIN IMPRVEMENT

16 16 ETFE Surface energy increase Very limited ageing after 3 weeks

17 17 Peel Force [N/m] ETFE Adhesion increase ETFE laminate (Araldite 2028) Untreated orona Plasma 1 Plasma 2 Plasma 3 Peel Force Surface Energy Surface energy [mn/m] Different plasma chemistries Surface energy is not the main factor improving adhesion

18 18 ETFE Adhesion increase Peel Force [N/m] ETFE laminate (Araldite 2028) Untreated orona Plasma 1 Plasma 2 Plasma 3 Peel Force %N grafted at. % N hemistry, not SE, is the main factor improving adhesion

19 19 PET Adhesion increase Peel Force [N/m] PET thermoset adhesive Untreated orona Plasma a Plasma b Plasma c Peel force Surface Energy Surface Enrgy [mn/m] Adhesion not always directly related to surface energy

20 20 PET Adhesion increase Peel Force [N/m] PET thermoset adhesive Untreated orona Plasma a Plasma b Plasma c At. % Nitrogen Peel force Surface omposition hemistry, not SE, is the main factor improving adhesion

21 21 Adhesion increase Acrylic PET Untreated vs orona 15% Untreated vs Plasma Up to 85% orona vs Plasma 35% Thermoset PET Untreated vs orona 200% Untreated vs Plasma Up to 2300% orona vs Plasma 800% Araldite 2028 ETFE Untreated vs orona 1000% Untreated vs Plasma Up to 4870% orona vs Plasma 350% Results depend on adhesive and plasma chemistries

22 22 onclusion Plasma treatment enables stable modification of surface energy Plasma allows to tailor the surface modifications to specific adhesive and substrate combination Level of adhesion can be controlled over a large range Plasma treatment can be applied to almost any materials (PEEK, Fluorinated polymers, PI, metals, paper )